Chain saw



FIG. 1 is a right side view of the ornamental appearance of the chain saw;

FIG. 2 is a left side view of the chain saw shown in FIG. 1;

FIG. 3 is a rear view of the chain saw shown in FIG. 1;

FIG. 4 is a top view of the chain saw shown in FIG. 1;

FIG. 5 is a left front perspective view of the chain saw shown in FIG. 1;

FIG. 6 is a top left perspective view of the chain saw shown in FIG. 1; and,

FIG. 7 is a top right perspective view of the chain saw shown in FIG. 1.

The broken lines shown in the drawings represent unclaimed portions of the chain saw and form no part of the claimed design.

Any surfaces of the design not shown, including interior or bottom surfaces, form no part of the claimed invention. 

I claim the ornamental design for a chain saw, as shown and described. 